The basics of the laminated object manufacturing process are illustrated in Feygin's U.S. Pat. Nos. 4,752,352 and 5,354,414. There it will be seen that, utilizing a three-dimensional computer-assisted design, a laser beam is directed onto sheets of paper coated with adhesive to cut cross-sectional patterns for layering. The machine quickly builds a three-dimensional object one sheet at a time, cross-hatching the unused parts of each sheet so they can be removed in small cubes or other three-dimensional geometric forms. When the laser beam finishes its work, the result is a "build", or coherent stack of paper which includes the sculpted object within a multiplicity of small cubes or other geometric forms. These cubes are pre-cut, but still must be chiseled to loosen them from the relatively coherent mass. Likewise, and most relevant for the present invention, the body of the sculpted object must be removed from the base on which it is placed.
In the typical commercial laser machine for laminated object manufacturing, or "LOM" machine, the object is built initially on an aluminum plate. A piece of wood or particle board, typically one-half inch to one inch thick, is fastened to the top of the aluminum, and then a layer of adhesive foam tape covers the wood or particle board. The primary purpose of the foam tape (usually about 0.06 inch thick, or about 0.01 to 0.2 inch thick) is to secure the base of the sculpted object so it will not shift, move or creep from vibration, or otherwise confound the very precise abilities of the laser beam to make accurate cuts. It is this foam tape on which the first pieces of paper are placed for laser beam impingement. Frequently, the operator will permit ten or twenty layers of paper to be placed by the machine on the foam tape or other low-density layer before the pattern of the sculpted object is begun. These sheets are cut by the laser in a geometric pattern such as in squares so that the construction of cubes of the unwanted portions is begun. The laser beam may or may not be employed to cross-hatch the foam tape. The machine then goes on to carve the paper, sheet by sheet, piling on successive cross sections of the sculpted object. When its task is complete, the user removes the wood or particle board base (sometimes called herein a portable base), on which the three-dimensional paper build is adhered, from the aluminum platform, and is faced with the task of liberating the sculpted object from the build, which of course includes the step of removing the build from the board base.
The build must be removed from the base without damaging the sculpted object. Frequently, attempts to remove the build using chisels and other simple hand tools has resulted in damage or distortion of the object. The sculpted object at this point represents a considerable investment in CAD input and LOM time. The irony of damaging such a valuable, and frequently intricate, product of high technology through the use of hand tools and manual strength is apparent.
Direct application of automated cutting devices--for example, a band saw--through the low-density layer results in fouling and gumming up. A simple sharp blade will also gum up, and a heated nichrome wire also fouls. The application of solvent to the relatively thin low-density layer is mechanically almost impossible. There is a need for a more reliable and safe way to remove the block from its base.